1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
|
// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef MEDIA_BASE_VIDEO_RENDERER_H_
#define MEDIA_BASE_VIDEO_RENDERER_H_
#include <list>
#include "base/callback.h"
#include "base/memory/ref_counted.h"
#include "base/time.h"
#include "media/base/media_export.h"
#include "media/base/pipeline_status.h"
namespace gfx {
class Size;
}
namespace media {
class DemuxerStream;
class VideoDecoder;
class MEDIA_EXPORT VideoRenderer
: public base::RefCountedThreadSafe<VideoRenderer> {
public:
typedef std::list<scoped_refptr<VideoDecoder> > VideoDecoderList;
// Used to update the pipeline's clock time. The parameter is the time that
// the clock should not exceed.
typedef base::Callback<void(base::TimeDelta)> TimeCB;
// Executed when the natural size of the video has changed.
typedef base::Callback<void(const gfx::Size& size)> NaturalSizeChangedCB;
// Used to query the current time or duration of the media.
typedef base::Callback<base::TimeDelta()> TimeDeltaCB;
// Initialize a VideoRenderer with the given DemuxerStream and
// VideoDecoderList, executing |init_cb| callback upon completion.
//
// |statistics_cb| is executed periodically with video rendering stats, such
// as dropped frames.
//
// |time_cb| is executed whenever time has advanced by way of video rendering.
//
// |size_changed_cb| is executed whenever the dimensions of the video has
// changed.
//
// |ended_cb| is executed when video rendering has reached the end of stream.
//
// |error_cb| is executed if an error was encountered.
//
// |get_time_cb| is used to query the current media playback time.
//
// |get_duration_cb| is used to query the media duration.
virtual void Initialize(const scoped_refptr<DemuxerStream>& stream,
const VideoDecoderList& decoders,
const PipelineStatusCB& init_cb,
const StatisticsCB& statistics_cb,
const TimeCB& time_cb,
const NaturalSizeChangedCB& size_changed_cb,
const base::Closure& ended_cb,
const PipelineStatusCB& error_cb,
const TimeDeltaCB& get_time_cb,
const TimeDeltaCB& get_duration_cb) = 0;
// Start audio decoding and rendering at the current playback rate, executing
// |callback| when playback is underway.
virtual void Play(const base::Closure& callback) = 0;
// Temporarily suspend decoding and rendering video, executing |callback| when
// playback has been suspended.
virtual void Pause(const base::Closure& callback) = 0;
// Discard any video data, executing |callback| when completed.
virtual void Flush(const base::Closure& callback) = 0;
// Start prerolling video data for samples starting at |time|, executing
// |callback| when completed.
//
// Only valid to call after a successful Initialize() or Flush().
virtual void Preroll(base::TimeDelta time,
const PipelineStatusCB& callback) = 0;
// Stop all operations in preparation for being deleted, executing |callback|
// when complete.
virtual void Stop(const base::Closure& callback) = 0;
// Updates the current playback rate.
virtual void SetPlaybackRate(float playback_rate) = 0;
protected:
friend class base::RefCountedThreadSafe<VideoRenderer>;
VideoRenderer();
virtual ~VideoRenderer();
private:
DISALLOW_COPY_AND_ASSIGN(VideoRenderer);
};
} // namespace media
#endif // MEDIA_BASE_VIDEO_RENDERER_H_
|